Closed cavity end concrete block mold



2 Sheets-Sheet. 1

IN VL'NTOE, E/w/z. FkA/VA Z 055?,

'JTTO/PNEYS.

March 17, .1942 E. F. ZUBER CLOSED CAVITY END CONCRETE BLOCK MOLD FiledAug. 22. 1940 Mazda 1? 1942. E. F. zuiaER 29 765 8 CLOSED CAVITY ENDCONCRETE BLOCK MOLD Filed Aug"; 22, 1940 2 Sheets-Sheet 2 Patented Mar.17, 1942 CLOSED CAVITY END CON CRETE BLOCK MOLD Emil Frank Zuber,Peoria, 111., assignor to The Michigan Silo Company, Kalamazoo, Mich, a

corporation of Michigan Application August 22, 1940, Serial No. 353,645

6 Claims.

This invention relates to means for forming a concrete building blockhaving the usual hollow cavities but, most importantly, having the topend solid across the upper ends of these cavities whereby the block maybe used for the top course in a foundation or wall so as to preventpassage of termites or the like from the ground up through the blocks tothe wooden structure thereabove.

The building code in some cities requires that on top of the last courseof concrete blocks there must be build a form at least one inch high andthis form filled with cement or concrete in order to form a concreteslab blocks. By use of my invention, this rather expensive operation offorming such a slab is avoided since the blocks may be molded directlyto have a solid top face.

A primary advantage of the invention is that the closed end-cavityblocks may be formed just as rapidly as the customary open end-cavityblocks and without distortion or change in shape and size. My inventioncontemplates the shortening of the core in the block mold thatforms thecavity so that the concrete may be formed directly over the ends of thecores presented. However, in order to make possible the removal of theblock from the cores or the cores from the block, means must beincorporated in the mold in conjunction with the cores to prevent thatpart of the concrete forming the closures over the,

cavities from being sucked downwardly into the cavity by reason of thevacuum otherwise produced. A further important advantage of theinvention is that there are no parts that have to be mechanicallyconnected with any timing or actual operating mechanism of the blockforming machine, since the structure forming the invention operatesautomatically.

These and many other objects and advantages of the invention will becomeapparent to those versed in the art in the following description of oneparticular form of the invention as illustrated in the accompanyingdrawings, wherein- Fig. 1 is a side elevation of a concrete filled blockmold, a portion of the side wall of the mold being removed;

Fig. 2, a similar view showing the block in a partially removedposition;

Fig. 3, a detail in side elevation and partial section of the blockcores;

Fig. 4, a top plan view;

Fig. 5, a transverse section through one core on the line -5 in Fig. 3;and

to seal off the hollow- Fig. 6, a vertical section on the line 6-6 inFig. 3. I

Like characters of reference indicate like parts throughout the severalviews in the drawings.

Referring to the drawings, the mold I0 is made in the usual and wellknown manner to carry a plurality of cores I I entering therein from theunder side, three such cores being shown to form the standard typeblock. Instead of continuing these cores to the top of the mold box l0,they are cut off to terminate by their upper ends at a distancetherebelow as indicated in Figs. 1 and 2. A plate I2 is placed on thetop end of each of the cores I I. This plate I2 has a peripherycoinciding with the periphery of the core at its top end so that theside of the plate I2 forms in efiect a continuation of the side wall ofthe core without any ofiset or projection therebetween.

In order to locate and maintain the plate I2 in alignment with its coreII, a stem I3 is fixed to the under side of the plate I2 and is carrieddown through a slot in the top end'of the core II. In order to preventrevolution of .the plate about the end of the core. I I, the stem [3 isformed in a rectangular shape to fit slidingly within a hole of likeconformation in the end of the core I I. Preferably the stem I3 extendsdownwardly within the core II a sufiicient distance to permit bending orotherwise deforming the lower end of the stem so as to limit the upwardtravel of the plate I2 from the core II. In the present form, the lowerend of the stem I3 is split and one side bent outwardly as indicated inFig. 6. Of course, the stem may be drilled through to receive a cotterpin I l as a stop. In any event the plate I2 is free to be lifted abovethe end of the core I l until the stop on the stem I3 arrests furthertravel.

The top end of each core II is provided with one or more air ventsor'holes l6, herein shown as two in number, one on each side. of thehole through which the stem I3 passes. The core II in each instance issecured to the floor I! of the mold by any suitable means, herein shownas by a cap screw I8 extending up through the floor I] andscrew-threadedly engaging a bar I9 extending transversely across thehollow interior of the core and being secured to the core wall on eachend byany suitable means, such as by welding. The core II in eachinstance is provided with a base air hole 20, here shown as in the lowerend of the side base or floor I1.

To use the invention, the cores above described wall immediately at theare positioned within the core box [0, as indicated in Figs. 1 and 2.Referring to Fig. 1, the cement or concrete is placed in the box Ill andtamped down in the usual manner to form the block as indicated. As willbe noted, the block is closed across its upper end by reason of thecores II and their plates l2 terminating at an elevation below the topof the box l so as to permit concrete or cement to be carried entirelyacross and over the upper ends of the cores II and their plates l2 sothat no opening is left in any instance from the top side of the block2| into the I top ends of the cavities formed by the cores I I.

Following the placing and tamping of the concrete, the block 2| isrelatively shifted upwardly in the usual manner so as to remove it fromthe box l0 and the cores H. Referring to Fig. 2, the block 2| is shownas having been shifted in relation to the box It a slight distance. Inthis initial shifting, it is to be noted that the plate l2 followsupwardly with the block due to the fact that a slight vacuum is createdwithin the space above the plates l2 and the under side of the concretewhich is in contact with the plate l2. The upper portion of the block 2|is thus supported and prevented from being pulled inwardly by the vacuumabove the cores as the block 2| is relatively moved from the cores.However, the slight initial upward travel of block 2| immediately clearsair holes 20 and air passes at once through these holes and upwardthrough holes IE to the space between cores II and plates 12; thence itfinds its way around the edges of plates 12 and relieves the partialvacuum between plates l2 and the concrete above plates [2. To facilitatethis air movement, the edges of plates I2 are beveled as shown. With thepartial vacuum removed, plates l2 immediately drop back down onto theends of cores H in every instance.

If the cores H are slightly tapered, as is quite customary to facilitatetheir withdrawal and as is shown in the drawings, then the initialrelative travel of block 2| away from cores H lets air also travel alongouter walls of cores H to reach the space between cores H and plates [2without passing through holes 29 and I6.

The stops on the stems I3, of course, prevent undue travel of the platesI2 away from their cores H as well as prevent misalignment therewith sothat the plates l2 are always automatically repositioned and ready foruse in subsequent molding operations.

While I have herein shown and described my invention in the oneparticular form, it is obvious that structural variations may beemployed without departing from the spirit of the invention and I,therefore, do not desire to be limited to that precise form beyond thelimitations as may be imposed by the following claims.

I claim:

1. In a concrete block mold, a core, a plate on the end of the core,said plate being shiftable in relation to the core in the direction ofthe axis of the core, means maintaining the plate in alignment with thecore, and stop means limiting the travel of the plate from the core.

2. In a concrete block mold, a core, a plate on the end of the core,said plate being shiftable in relation to the core in the direction ofthe axis of the core, means maintaining the plate in alignment with thecore, and stop means limiting the travel of the plate from the core,said core having one or more air vents in said end under said plate.

3. In a concrete block mold, a core, a plate on the end of the core,said plate being shiftable in relation to the core in the direction ofthe axis of the core, means maintaining the plate in alignment with thecore, and stop means limiting the travel of the plate from the core,said core having an air vent in its side wall at its base.

4, In a concrete block mold, a core, a plate on the end of the core,said plate being shiftable in relation to the core in the direction ofthe axis of the core, means maintaining the plate in alignment with thecore, and stop means limiting the travel of the plate from the core,said core having one or more air vents in said end under said plate,said core having an air vent in its side wall at its base.

5. For molding plastic articles to have a cavity therein opening fromone side of the article and closed at the other side, a tapered corehaving an outer transverse end wall shiftable in relation to the core inthe direction of the axis of the core, said core having one or more airvents through the core opening under said wall, whereby relativemovement between the article molded over the core and the core for corewithdrawal allows said wall to move initially with the article until thecavity is vented through said vent.

6. For molding plastic articles to have a cavity therein opening fromone side of the article and closed at the other side, a core having anouter transverse end wall shiftable in relation to the core in thedirection of the axis of the core, whereby relative movement between thearticle molded 'over the core and the core for core withdrawal allowssaid wall to move initially with the article until the cavity is vented.

EMIL FRANK ZUBER.

